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By C. K. Eilerts

Finite difference equations were programmed and used to integrate the second-order, second-degree, partial differential equation with variable coefficients that represents the transient linear flow of gas-condensate fluids. Effect was given to the change with pressure of the compressibility factor, the viscosity, and the effective permeability and to change of the absolute permeability with distance. Integrations used as illustrations include recovery of fluid from a reservoir at a constant production rate followed by recovery at a declining rate calculated to maintain a constant pressure at the producing boundary. The time required to attain such a limiting pressure and the fraction of the reserve recovered in that time vary markedly with properties of the fluid represented by the coefficients. Fluid also is returned to the reservoir at a constant rate, until initial formation pressure is attained at the input boundary, and then at a calculated rate that will maintain but not exceed the limiting pressure. The computing programs were used to calculate the results that would be obtained in a series of back-pressure tests made at selected intervals of reservoir depletion. If effect is given to the variations in properties of the fluid that actually occur, then a series of back- pressure curves — one for each stage of reserve depletion — is required to indicate open-flow capacity and related flow characteristics dependably. The isochronal performnce method for determining flow characteristics of a well was simulated by computation. INTRODUCTION The back-pressure test procedurel is based on a derivation of the equation for steady-state radial flow of a gas, the properties of which are of necessity assumed to remain unchanged in applying the test results. The properties of most natural gases being recovered from reservoirs change as the reserve is depleted and pressures decline, and the results of an early back-pressure test may not be dependable for estimating the future delivery capacity of a well. The compressibility factor of a fluid under an initial pressure of 10,000 psia can change 45 per cent and the viscosity can change 70 per cent during the productive life of the reservoir. There are indications that the effective permeability to the flowing fluid can become 50 per cent of the original absolute permeability before enough liquid collects in the structure about a well as pressure declines to permit flow of liquid into the well. The advent of programmed electronic computing made practicable the integration of nonlinear, second-order, partial differentia1 equations2.3 pertaining to flow in reservoirs. Aronofsky and Porter4 represented the compressibility factor and the viscosity by a linear relationship, and integrated the equation for radial flow of gas for pressures up to 1,200 psi. Bruce, Peaceman, Rachford and Rice5 integrated the partial differential equations for both linear and radial unsteady-state flow of ideal gas in porous media. Their published results were a substantial guide in this study of integration of the partial differential equation of linear flow with coefficients of the equation variable. The computing program was developed to treat effective permeability as being both distance-dependent and pressure-dependent. In this study all examples of effective permeability are assumptions designed primarily to aid in developing programs for giving effect to this and other variable coefficients. The accumulation of data for expressing the pressure dependency of the effective permeability is the objective of a concurrent investigation. FUNDAMENTAL DIFFERENTIAL EQUATIONS DIFFERENTIAL EQUATION OF FLOW Linear transient fluid flow is represented by the partial differential equation,

Jan 1, 1965

By K. H. Nimerick, B. E. Scott, F. J. Beafore

A unique freeze conditioning agent (FCA) which functions by forming structurally weak ice rather than suppressing the freezing point of water has been successful in alleviating frozen coal problems. Frozen coal treated with FCA has been quickly unloaded at temperatures below -17.8°C (O°F). Other applications of FCA include deicing: conveyor belts, idler, idler arms, and other moving parts that have been impeded by ice.

Jan 9, 1979

James Gayley, Braddock, Pa. (communication to the Secretary) : Mr. Potter has made reference to our practice at the Edgar Thomson works in the direction of increasing the life of the lining, and mentions the product of one of our furnaces as having reached a total of 370,000 tons. It may be interesting to know that this furnace has been put out of blast with a record of 452,685 tons, after a run of three years and nine months. A companion-furnace to this will produce, hefore the present year is ended, half a million tons. As Mr. Potter has quite correctly designated this as " the newest problem in furnace-practice," a description of the construction of this furnace lining may be Welcome to members. The bricks used in the lining are 9 and 134 inches long, with the requisite quantity of straight and key-shapes to turn the circle. There bricks are well suited for enclosing the numerous bosh-plates used for cooling. The bosh-plates (the efficient fortress of the lining) extend from the top of the tuyere arch to the mantel, and are inserted in rows, 18 inches to 2 feet apart. These form a perfect defence against encroachment on the bosh-lining, and leave the bosh at the end of the blast of the same thickness as at the beginning. The protection afforded by these bosh plates is the principal cause of the increased duration of the furnace-lining. But it must be noted that the shape and material of the plate are essential elements. The most serviceable plate is that made of bronze or copper. We have tried every form of iron plates without obtaining satisfactory results. These were replaced with bronze plates, built into the lining, which gave excellent results so long as they did not leak; but when this occurred, as it did in time, the water was shut off, and, since the plates could only be removed with difficulty, they were allowed to burn off. This permitted encroachment on the bosh-walls, which thus became enlarged beyond the limit required for economical practice. With the introduction of the removable plate, made tapering on the sides, with plain surfaced top and bottom, these troubles have

Jan 1, 1895

By Chase Palmer, Edson S. Bastin

While the reducing action of organic matter, of ferrous sulphate, and of hydrogen sulphide has frequently been invoked to account for the deposition of native gold and silver from ore-forming solutions, the high efficiency in this respect of certain of the metallic minerals which form the ore itself has not been suffciently recognized. If a little finely powdered chalcocite is placed in a test-tube arid 2 or 3 cc. of a dilute solution of gold chloride are poured over it, two or three shakes of the tube suffice to remove all the gold from the solution. The color of the solution changes from yellow to pale green, showing that copper is dissolved simultaneously with the precipitation of metallic gold. If a piece of chalcocite is hung in a dilute aqueous solution of silver sulphate (1/40 normal), a coating of silver begins immediately to form on the mineral, and within a few moments a beautiful silver tree has developed, similar to that formed when metallic zinc is immersed in a similar solution. When similar experiments are conducted with other sulphides and with certain arsenides and sulph-arsenides, especially those known to be commonly associated with native silver in ore deposits, it is found that these minerals differ greatly in their efficiency as precipitants, especially in their effect on silver solutions. The tests made with most of the minerals were qualitatipe only, but the reactions of a silver sulphate solution on chalcocite and niccolite were submitted to quantitative study to determine the nature of the reactions involved. Quantitative studies of the reactions with other minerals are now in progress

Jan 1, 1914

By Alan Probert

IN his inaugural address in 1949, President Truman made a policy declaration which launched the foreign technical assistance program known to the world as Point Four. Congress passed Public Law 535 defining the scope of the program and holding activities to certain limitations. It also provided $34.5 million for the first fiscal year. The Technical Cooperation Administration was established within the Department of State to coordinate and direct a program to include "economic, engineering, medical, educational, agricultural, fishery, mineral and fiscal surveys, demonstration, training and similar projects." The mineral programs of Point Four have been staffed and managed by two agencies of the Department of Interior, the Geological Survey and the Bureau of Mines. The Geological Survey is concerned primarily with water-supply problems, the discovery of mineral deposits, and the determination of habit, shape, and grade of mineral deposits. The Bureau of Mines is concerned with determining the commercial potentialities of mineral deposits, mineral technology, and the production and distribution of mineral commodities. Mineral projects comprised only 1 pet of the first year's budget. In spite of the relatively insignificant expenditure compared to those for food, agriculture, and health, a commendable record has been achieved.

Jan 1, 1952

By J. O. Nomland

DuRing the year 1939 the program of the California Arabian Standard Oil Co. in eastern Saudi Arabia consisted of drilling wells to increase the production of Dammam Dome. (This structure is also sometimes referred to as Dhahran Dome.) In addition, in other areas of the concession, wildcat wells are being drilled on geologically favorable structures. In the early wells drilled at Dhahran, production was at a depth of 2000 to 2200 ft. Since discovery of the "Arab zone" below 4300 ft., all of the later wells have been drilled to the deeper productive members. At present there are at Dhahran fivc wells in various stages of drilling or completion. In addition, 15 wells previously were drilled to the upper or lower zones. Although some of the early locations are exceptions, in general the spacing of the wells is at 3000 feet. Prospect testing consisted in drilling one well at Abu Hadriya and one at Ma'agala, about 100 miles northwest and 120 miles west of Dhahran. The first had attained a depth of 8655 ft. without encountering the main Darnmam productive zone, while the second was at a depth of 1372 ft. Both of these wildcat wells are on large dome structures. Production.—During the year 3,933,903 bbl. of approximately 35" gravity oil was produced, all from flowing wells. A part of this production was shipped in barges to the refinery at Bahrein. In early May a 40-mile 10-in. pipe line was completed to the deep-water terminal at Ras Tanura. The ceremony of first opening the valve for flow of oil into an ocean tanker was performed by King Abdulaziz Ibn Saud. Since that time tanker shipments have continued, both to Bahrein and to world markets. Only sufficient gas for camp purposes has been produced. Equipment.—A stabilization plant has been completed at Dhahran and plans have been made for a refinery at Ras Tanura. A modern camp is being built including power plant, central air-conditioning plant, radio station, employees' club and housing facilities for both married and single employees. Both the offices and dwellings are being air-conditioned. There is a hospital, with medical staff and nurses, providing facilities for both Saudi Arabs and Americans.

Jan 1, 1940

By J. O. Nomland

DuRing the year 1939 the program of the California Arabian Standard Oil Co. in eastern Saudi Arabia consisted of drilling wells to increase the production of Dammam Dome. (This structure is also sometimes referred to as Dhahran Dome.) In addition, in other areas of the concession, wildcat wells are being drilled on geologically favorable structures. In the early wells drilled at Dhahran, production was at a depth of 2000 to 2200 ft. Since discovery of the "Arab zone" below 4300 ft., all of the later wells have been drilled to the deeper productive members. At present there are at Dhahran fivc wells in various stages of drilling or completion. In addition, 15 wells previously were drilled to the upper or lower zones. Although some of the early locations are exceptions, in general the spacing of the wells is at 3000 feet. Prospect testing consisted in drilling one well at Abu Hadriya and one at Ma'agala, about 100 miles northwest and 120 miles west of Dhahran. The first had attained a depth of 8655 ft. without encountering the main Darnmam productive zone, while the second was at a depth of 1372 ft. Both of these wildcat wells are on large dome structures. Production.—During the year 3,933,903 bbl. of approximately 35" gravity oil was produced, all from flowing wells. A part of this production was shipped in barges to the refinery at Bahrein. In early May a 40-mile 10-in. pipe line was completed to the deep-water terminal at Ras Tanura. The ceremony of first opening the valve for flow of oil into an ocean tanker was performed by King Abdulaziz Ibn Saud. Since that time tanker shipments have continued, both to Bahrein and to world markets. Only sufficient gas for camp purposes has been produced. Equipment.—A stabilization plant has been completed at Dhahran and plans have been made for a refinery at Ras Tanura. A modern camp is being built including power plant, central air-conditioning plant, radio station, employees' club and housing facilities for both married and single employees. Both the offices and dwellings are being air-conditioned. There is a hospital, with medical staff and nurses, providing facilities for both Saudi Arabs and Americans.

Jan 1, 1940

By Frank Firmstone

(Ottawa Meeting, October, 1889. Substituted for the briefer note on the same subject. pre sented at the meeting and subsequently distributed in preliminary pamphlet edition.) Prof. H. Hoefer's theory of blasting was published in the Oesterr. Zeitschrift, xxviii., 1880, and xxix., 1881; and Part 111. in Nos. 15, 16 and 17, xxx., 1882, and subsequent numbers of that

Jan 1, 1890

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Jan 1, 1938

By William M. Shepard

The Tintic mining districts of central Utah com- prise one of the major silver-lead producing areas in the United States. Ore valued at nearly $450 million has been produced from these districts since the initial discoveries, in 1869, of veins cutting the Silver City monzonite stock. Subsequent production from the famous manto-type "ore runs", which characterize the Main Tintic district, was followed during the past 40 years by discovery of the blind orebodies of the East Tintic district, including the famous Tintic Standard mine and the most recent discovery, the Burgin mine, currently being brought to full production by Kennecott Copper. The occurrence of blind orebodies of exceptional size and grade in both the Main and East Tintic districts has made this area a field laboratory of major importance for the study of geochemical dispersion halos and alteration features associated with known ore, and has led to the discovery of additional concealed orebodies. The larger share of the basic data-gathering and interpretation has been done by members of the U.S. Geological Survey who have been studying the Tintic mining areas since before the turn of the century. These studies have been supplemented and expanded by the geological staffs of the local operating mining companies, by exploration geologists and by students.

Jan 4, 1966

By Kenneth A. Grace

Jan 1, 1985

By J. F. Pashak, T. E. Leontis

The effects of zirconium on the properties of sand cast Mg-rare earth metal alloys were discussed in detail in an earlier publication.' It was shown that a significant improvement in strength properties at temperatures up to 400°F resulted from the zirconium addition. In general, the properties of cast Mg-Didymium-Zr alloys were superior to the corresponding alloys containing Mischmetal and the optimum rare-earth level was approAmately 3 pet. Jessup, Emley, and Fisher have also shown the advantages of didymium in Mg-rare earth-Zr alloys, 2

Jan 1, 1961

By Roberto Pimentel de Souza, Helder Zenóbio

VRD started producing pellets in 1969 with one 2-million-t straight grate plant. In the beginning of April 1973, the second unit came on stream with an additional capacity of 3 million t/a of pellets. In January 1977, the third unit started, bringing the annual capacity to 8 million t/a. In the coming year (1978-79), three more units, 3 million t each, are expected to begin production. CVRD's experience with different binders and additives is described. Over the years several kinds of pellets have been produced to satisfy market requirements. General quality information is given for each.

Jan 1, 1981

By Henry Fernald

THE accounting system or bookkeeping methods of any company are principally the concern of that company and of those who are in control of its affairs. Its published financial report is, however, primarily intended for those who are not already fully informed regarding its operations and finances. Whatever may be the advantages of standardization of accounting and bookkeeping methods, it must be admitted that a company has a certain right to handle its accounts and keep its books and records in whatever manner may seem to it best adapted to its affairs, even though such methods may differ materially from those generally adopted by others. In its financial reports it should not, however, either ask or expect that the statements it makes or the terms which it uses will be given in its case a meaning and interpretation different from that which they are ordinarily considered to have inn similar reports and statements of other companies. The particular form and arrangement of such reports is a matter concerning which there may be much difference of opinion. It is of little importance whether current assets come first or last in the Balance Sheet, but it is important that there should not be included under this designation any items which are not properly current assets within the generally accepted meaning of that term. The extent to which stockholders or others interested are to be made acquainted with the full details of a company's business is a question which the proper authorities must in each case decide. It should, however, be recognized that there are certain facts regarding a mining company which must be set forth in a financial statement if it is fully to cover the conditions and affairs of the company. For example, a financial statement which does not include or is not accompanied by a statement of the ore reserves of the company does not fully set forth its financial condition. This is true whether the absence of such a statement of ore reserves is because it is not desired to make public the figures or whether it is because the ore reserves themselves are not definitely known or accurately measured.

Jan 1, 1928

By G. S. Scott, G. W. Jones

ECONOMIC waste caused by mine fires may become considerable,15 especially if a fire is allowed to spread or temporarily to get beyond control. It is important, therefore, to act promptly whenever a fire is suspected and to make every action count. To contribute toward its extinction effectively it is necessary to know at the earliest possible moment, and continuously thereafter, what is happening at the seat of the fire, which may be in a remote or inaccessible area, and also to recognize what may be expected as a result of any proposed combative measure. In combatting a fire the mining engineer and the chemist should cooperate, first deciding upon the course of action to be taken and then drawing upon the mining engineer's intimate knowledge of the physical structure of the fire area, the cost and time required to carry out proposed operations, and the probable efficiency with which these operations could be performed, and upon the chemist's knowledge for the results to be expected therefrom. After the initial steps to be taken have been decided, it devolves upon the mining engineer to see that they are carried out and upon the chemist to evaluate the results and to keep the mining engineer continuously informed in regard to a variety of matters-such as the composition and toxic or asphyxiating properties of the atmosphere in which the men may be working, whether the fire is increasing or decreasing in intensity and its probable temperature, the quantity of air leakage and the explosion hazards of the fire area. The purpose of this paper is to discuss what the chemist can and cannot contribute as a member of the fire-fighting personnel. The technical literature contains several hundred papers relating directly and indirectly to mine fires, and this fact alone is testimony to the complex nature of the phenomena involved in the birth, life, and final demise of a fire. A fire may be stopped (I) by preventing oxygen from reaching the coal or (2) by removing the conditions necessary for the rapid reaction of coal with oxygen; i.e., decreasing the temperature. All methods of prevention or control. necessarily must be based upon one or the other, or both, of these two principles. . The chemistry of a fire may be understood readily if the low-temperature oxidation of coal is considered as a starting point; then oxidation at higher temperatures (or combustion) ; and with these, the composition of the solid and gaseous products resulting from the oxidation or from the effects of the heat liberated. This discussion refers particularly to Pennsylvania anthracite, although much of the material applies equally well to coals of lower rank. OXIDATION OF COAL Oxidation of coal fundamentally is confined to the surface; that is, the rate at which oxygen penetrates into the interior of a solid block of coal is so slow that it may be ignored.6,16 Oxidation starts when a fresh surface is exposed, and the rate is

Jan 1, 1942

By Arthur J. Boynton

In the preparation of this paper the writer has been influenced by the fact that descriptions of various means of cleaning blast-furnace gas have been published and that further descriptive treatment of the subject will probably be less interesting than a statement of conclusions with regard to preferable methods which have been reached by him as a result of experience and observation in this country and also as a result of somewhat detailed investigation of the subject made toward the end of the year 1927 on the Continent of Europe and particularly in Germany. Owing to various circumstances, including a cost of fuel that is extremely high in relation to the wages of labor, the German iron and steel industry has accumulated experience in gas washing which is as yet in part lacking in the United States of America. The paper begins with a statement regarding the economics of the use of blast-furnace gas, then considers the principles and practices employed in its purification. Uses of Blast-furnace Gas For many reasons having to do with the utilization of coke-oven and blast-furnace gases in steel manufacture and with the use of hot metal, the blast furnace is now usually a part of a steel-producing unit, which also includes coke plant and rolling mill. Therefore both blast-furnace and coke-oven gas are usually applicable to any of the iron and steel-making processes, including the generation of power, and their allocation in any given works should be considered as a single problem. The uses to which blast-furnace gas, either alone or mixed with coke-oven gas may be put, include the following: Regenerative Heating of Ail. for the Blast Furnace.—This is the oldest and metallurgically the rnost important of all uses. It is universally performed with unmixed blast-furnace gas and under proper conditions should require not over 23.5 per cent. of the total gas generated for a blast temperature of 1350" F. For Steam-raising Purposes.—This is almost universally done with unmixed blast-furnace gas. From the standpoint of quantity used, it is at the present time the most important application in American steelworks practice.

By J. Szekely, R. G. Carr

A method is presented which allows the extension of the Ergun equation for the description of gas flow through packed beds in a nonisothermal regime. The pressure profile in the packed bed is calculated by the establishment of a differential energy balance and the iterative integration of the integral equation thus obtained. The predicted values of the pressure distribution were found to be in excellent agreement with those measured experimentally, under carefully controlled conditions. MANY metallurgical processes are carried out in systems in which a gas stream and particular solids are contacted in a packed bed arrangement under strongly nonisothermal conditions. Ore sintering, the firing of pellets, the operation of regenerators, blast furnace technology may be quoted as examples. Although many aspects of these systems have been extensively studied, an important variable, the pressure distribution and the relationship between pressure head and flow rate, received only little attention to date. The purpose of the paper is to present a brief survey of relevant previous work, followed by a more rigorously formulated model, together with experimental results that afford ready comparison of theoretical prediction with measurement. PREVIOUS WORK A great deal of information is available in the chemical engineering literature on flow phenomena in porous media.' The experimental results pertaining to gas flow were generally interpreted in terms of models based on the analogy with the flow through a pipe of an incompressible, isothermal fluid. Of the numerous, semiempirical correlations that have been proposed to relate pressure drop to the volumetric flow rate, the Ergun equation2 is generally regarded as the most satisfactory: The strong nonisothermality of the metallurgical systems previously mentioned would render the direct applicability of Eq. [I] rather doubtful as both density and viscosity are temperature-dependent. Ergun has used Eq. [I] for estimating the pressure drop in the stack region in the blast furnace by neglecting the viscous term and evaluating the gas density at the integral mean temperature.3 His calculations showed a rather variable agreement with measurements and it was uncertain whether the discrepancy found was attributable to the model or to the inaccuracies often inherent in measurements on an industrial scale. Other work on nonisothermal systems includes studies of the pressure distribution in sinter beds, notably by Voice et a1.4 and Mitchell.5 Mitchell developed a method involving the subdivision of the bed into several zones and assigning average property values (temperature, gas density, and so forth) to each zone. The pressure drop was then calculated for each zone by using an expression analogous to Eq. [I]. This method was an improvement over that described by Voice et al., but even here prediction and measurement differed by as much as 30 pct in certain cases. It would appear that no really satisfactory methods are available for the prediction of pressure drop in packed beds with a strongly nonisothermal regime. The method involving subdivision of the bed into small enough sections, that may be regarded as isothermal, would show promise; however its validity has to be tested by both a rigorous formulation and comparison with experimental data obtained under controlled conditions. In the following a formulation is presented together with experimental data allowing ready practical evaluation of the theory. FORMULATION The mechanical energy balance over an infinitesimal section of a packed bed may be written as follows:

Jan 1, 1969

By E. H. Bronson

PROPERTY of Malartic Gold Fields Ltd. is situa-ated in the great clay belt in the northern part of the Province of Quebec. This belt represents the floor of the glacial lake Barlow-Ojibway. The clay blanket has a gently rolling, almost flat surface, with here and there projecting knobs and ridges that outline the large irregularities of the surface on which the clay was deposited. At irregular intervals glacial eskers dominate the landscape. The ore-bearing country rock is covered by strata of clay, sand, and silt to a depth varying to 40 ft. There are serious structural problems when it is necessary to place loads of unequal intensities on this surface to support buildings and machinery for a modern mining plant. Earlier mining companies and their engineers paid little attention to the science of soil mechanics, partly because they believed it unnecessary and partly because they knew little of the subject. The results are evident in some of the tottering structures in older camps. Careful analysis of soil problems is well worth-while, since cost of foundations may vary from 20 to 50 pct of the final cost of a structure. Low operating and maintenance costs can be achieved only in this way. If it is definitely established that a plant will be in operation for only a few months, this limited time factor will probably influence the design of the foundation, and rightly so. If sensitive and complickted equipment is to be mounted on these foundations and the plant is to operate for several years, there should be a thorough study of foundations and a very careful design. A familiar problem is presented by the difficulty of operating a permanent plant originally designed for a few months' work. The engineer must beware of these hazards and disassociate himself from them if he cannot prevail on the promoter to spend the proper amount for a thorough foundation study. Laws of certain provinces and states hold the engineer equally responsible with the contractor for any 'damage that may be caused to building through inadequate study-ignordnce of the facts is no excuse in the eyes of the law. Types of Soil: The engineer should be familiar with such terms as silt, clay, peat, and varved clay, as well as perpafrost, especially if he is to work in the far northern reaches of the country. He should also be familiar with soil attributes such as porosity, texture, consistency, permeability, compressibility, consolidation, and shearing resistance. The design of any foundation requires an accurate knowledge of the physical properties and location of the soils involved. Older textbooks on the subject outline various empirical methods to determine the carrying power of soil. Tables are given in reference books. The modern ehgineer should be wary of these modes of thinking. He should analyze his problem carefully, calculate to what depth of soil the loads may be transmitted, and then check the bearing value of all soils to that or greater depths. If the strata are water-carrying, he must determine the possibility of this water being accidentally re-

Jan 1, 1958

By R. Hogg, F. F. Aplan, P. B. Bradley, M. F. Placha

Particle size distributions of the solids fraction in typical coal preparation plant black water have been evaluated. The carbonaceous and mineral fractions were found to have distinctly different size distributions: the mineral matter being significantly finer than the carbonaceous material in all cases. Based on analyses of 13 samples obtained from the Appalachian, mid-continent and western regions of the US, it was found that, on the average, 83% of the mineral particles but only 41 % of the coal particles were finer than 44 pm (325 mesh). Typically, the size distributions of the mineral matter fraction tend to be bimodal, probably due to the presence of relatively coarse quartz, calcite, pyrite, etc., together with much finer clay particles.

Jan 1, 1981

By Garfield Schnee

MACHINERY has not taken the place of manual labor in steep pitch coal in the anthracite field and there is a shortage of miners experienced in this type of work. To overcome these difficulties several coal companies have resorted to different types of mining such as the diamond or zig-zag method, the slant method, long hole drilling, and several other variations. For the past 5 years the diamond shape method has been used extensively in the heavy pitching beds of both the Knickerbocker and Yatesville basins at Knickerbocker colliery of the Philadelphia & Reading Coal & Iron Co.

Jan 10, 1950